Parks Canada warns of dangerous surf conditions at P.E.I. National Park

Surf conditions at three of the most popular beaches at P.E.I. National Park Cavendish, North Rustico and Greenwich beaches are being rated as dangerous, Parks Canada warned Wednesday.

"For your own safety, visitors are advised not to enter the water," the agency said on its Facebook page, citing the danger from rip currents.

Those are a hazard that form when waves break near the shoreline, piling up water between the breaking waves and the beach.Swimmers can become trapped in the rapid current and be swept offshore.

Stanhope and Brackley beaches were considered to pose a moderate risk on Wednesday, the post said.

"Exercise caution and swim only within your limits as rip currents are present," Parks Canada said in the post."Supervised swimming areas are recommended."

If you are caught in a rip current, it's recommended youstay calm, tread water and conserve energy while attracting attention. Swimmers can also try to swim parallelto the shore to break out of the current.

The best defence against a rip current is to stay on the beach.

The danger is particularly high on beaches that do not have lifeguards on duty.